Tank-Mixing for Effective Foliar Fertilization
As the direct spray applica- tion of plant-available nutrients, foliar fertilization is used to (1) quickly reverse nutrient deficiencies, (2) enhance the uptake of soluble nutrient forms that are incompatible with current soil chemical conditions and/or (3) uniformly deliver low rates of nutrients. In-season, foliar treatment of golf course putting greens is a particularly well-suited alternative to the application of persistent, granular fertilizers. Likewise, frequent foliar fertilization by soluble nitrogen (N) supports consistent growth instead of peaks and troughs in N sufficiency.
An important objective of foliar fertilization is the uniform application of plant-available nutrients. The tank-mix compatibility of combined liquid/soluble fertilizers, however, should not be assumed; while tank-mix incompatibility is far less a problem than it used to be, it does still affect this important objective. The degree to which uniform plant-available nutrient delivery is compromised varies. Do you remember those first-generation sprayers that were equipped with only a tank, pump, spray boom and regulator? If you ever used one and were certain that you calibrated it properly and operated it at the planned speed to accurately treat the given area, only to discover 15% to 40% of the original tank mix remaining in the tank when finished, you’ve experienced screen-clogging.